美团，求大佬，被7整除（10%）， 关灯泡（40%， 超时）

int count1(int num) {
    int count = 0;
    while (num) {
        num = num & (num - 1);
        count++;
    }
    return count;
}

int solve(int num, vector<string>& vec, int n) {
    int index1 = -1, index2 = -1;
    for (int i = 0; i < n; i++) {
        if (num & 1) {
            if (index1 == -1) {
                index1 = i;
            } else if (index2 == -1) {
                index2 = i;
            } else break;
        }
        num = num >> 1;
    }

    int count = 0;
    long long res1 = stoll(vec[index1] + vec[index2]);
    long long res2 = stoll(vec[index2] + vec[index1]);
    if (res1 % 7 == 0) count++;
    if (res2 % 7 == 0) count++;
    return count;

}

int main() {
    int n;
    while (~(scanf("%d", &n))) {
        vector<string> vec(n, "");
        long long count = 0;
        for (int i = 0; i < n; i++) cin >> vec[i];
        for (int i = 0; i < (1<<n); i++) {
            if (count1(i) == 2) {
                count += solve(i, vec, n);
            }
        }
        printf("%lld\n", count);
    }
    return 0;
}

bool helperFirst(vector<int>& vec, int index) {
    for (int i = index; i < vec.size(); i++) {
        if (vec[i] == 1) vec[i] = 0;
        else vec[i] = 1;
    }
    bool flag = true;
    for (int i = 0; i < vec.size(); i++) {
        if (vec[i] == 1) {
            flag = false;
            break;
        }
    }
    if (flag) return flag;

    for (int i = 0; i < vec.size(); i++) {
        if (vec[i]) {
            if (helperFirst(vec, i)) {
                flag = false;
                break;
            }
        }
    }
    return flag;
}

int main() {
    int n;
    while (cin >> n) {
        vector<int> vec(n, 0);
        for (int i = 0; i < n; i++) cin >> vec[i];
        int flag = false;
        for (int i = 0; i < n; i++) {
            if (vec[i]) {
                if (helperFirst(vec, i)) {
                    flag = true;
                    break;
                }
            }
        }
        if (flag) cout << "Alice" << endl;
        else cout << "Bob" << endl;
    }
    return 0;
}